Commit 1c3b9091 authored Nov 10, 2021 by Peter Zijlstra

x86/fpu: Remove .fixup usage



Employ EX_TYPE_EFAULT_REG to store '-EFAULT' into the %[err] register
on exception. All the callers only ever test for 0, so the change
from -1 to -EFAULT is immaterial.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/20211110101325.604494664@infradead.org

parent e2b48e43

arch/x86/kernel/fpu/legacy.h

+1 −5

Original line number	Diff line number	Diff line
		@@ -35,11 +35,7 @@ static inline void ldmxcsr(u32 mxcsr)
		int err; \
		asm volatile("1:" #insn "\n\t" \
		"2:\n" \
		".section .fixup,\"ax\"\n" \
		"3: movl $-1,%[err]\n" \
		" jmp 2b\n" \
		".previous\n" \
		_ASM_EXTABLE(1b, 3b) \
		_ASM_EXTABLE_TYPE_REG(1b, 2b, EX_TYPE_EFAULT_REG, %[err]) \
		: [err] "=r" (err), output \
		: "0"(0), input); \
		err; \

arch/x86/kernel/fpu/xstate.h

+1 −5

Original line number	Diff line number	Diff line
		@@ -108,11 +108,7 @@ static inline u64 xfeatures_mask_independent(void)
		"\n" \
		"xor %[err], %[err]\n" \
		"3:\n" \
		".pushsection .fixup,\"ax\"\n" \
		"4: movl $-2, %[err]\n" \
		"jmp 3b\n" \
		".popsection\n" \
		_ASM_EXTABLE(661b, 4b) \
		_ASM_EXTABLE_TYPE_REG(661b, 3b, EX_TYPE_EFAULT_REG, %[err]) \
		: [err] "=r" (err) \
		: "D" (st), "m" (*st), "a" (lmask), "d" (hmask) \
		: "memory")